Toni tells Claude that he wants him to destroy two vans used by Mr. Wong's Laundromat, after the Triads had attempted to ambush him before. Toni tells Claude to drop by 8-Ball'sEightballs Autoyard in Saint Mark's to collect some grenades. After leaving Toni, Claude locates and destroys the three vans (two vans in the 10th Anniversary Edition), avoiding pursuing Triads after destroying the first van.
Although the mission implies that you destroy the vans with grenades, is not really necessary do this. In truth, it is much easier to fulfill the mission by using Drive-By Shooting with an Uzi or stealing the three vans and destroy them at the same time pushing them to the ocean. If you want to use this technique, it is also important that you know: you must steal the vans by stopping a car in front of them carefully. If you hit your car or shoot at the vans, the drivers perceive that they are being pursued and will drive away quickly, making it very difficult to rob them.
Use the grenades to destroy the vans is a very bad idea because it draw police attention quickly, the technique above is recommended if you want to economize the grenades to use them later and avoid the aggressive Triads. Just as they start to attack you only if destroy one of the vans, merely stealing them will not make them to attack you.
After the introduction cutscene, the vans are located in the heart of Chinatown and begin to branch out to other parts in Portland. It is recommended to drive there quickly because there is a possibility that the vans could intersect paths at one point, making it quicker to finish the mission.